NEOS Interfaces to Bonmin

The NEOS Server offers Bonmin (Basic Open-source
Nonlinear Mixed INteger programming)
for the solution of mixed integer
nonlinearly constrained optimization problems in
AMPL
format. Bonmin is also available open source under the
Common Public License

Bonmin was developed by a large team of researchers at IBM and
Carnegie Mellon:

Pierre Bonami,

Lorenz Biegler,

Andrew Conn,

Gerard Cornuejols,

Ignacio Grossmann,

Carl Laird,

Jon Lee,

Andrea Lodi,

Francois Margot,

Nicolas Sawaya, and

Andreas Waechter.

An introduction to Bonmin can be found on
the Bonmin project home page at
COIN-OR.
Bonmin is a hybrid between two classical algorithms for
mixed integer nonlinear programming: an outer-approximation-based
branch-and-cut-based algorithm and a pure branch-and-bound algorithm.
The user can set options to declare which version of the algorithm
should be employed through NEOS.

Using the NEOS Server for Bonmin

The user must submit a model in
AMPL
format to solve a mixed integer nonlinearly constrained optimization problem.
Examples of models in AMPL format can be found in the
MINLP-AMPL library.

The model is specified by a model file, and optionally,
a data file and a commands file. If the command file is specified
it must contain the AMPL solve command.

Setting Options for Bonmin

Bonmin has a variety of options that can alter the algorithm behavior.
The
User's
Manual for Bonmin describes all the solver options available to
the user. There are two ways to set options to Bonmin though
NEOS. First, the (AMPL)
commands file can contain AMPL commands to set options for Bonmin.
Second, the user can specify the name of a local options file
bonmin.opt that will be used.

Printing directed to standard out is returned
to the user with the output.